The present invention relates to apparatus and method for the launching and the recovery of a sub-ordinate vehicle by host vehicle and, more particularly, to the launching and recovery of sub-ordinate seaborne surface and/or sub-surface vessels by a host seaborne surface and/or sub-surface vessel.
Various seaborne systems are known by which a host vessel can launch a sub-ordinate vessel and by which the host vessel can recover a sub-ordinate vessel. For example, remotely operated vessels, including submersible vessels, can be merely lifted from the deck of the host vessel by a crane of some type and placed on the surface of the water and, conversely, lifted from the surface of the water onto the deck of host vessel. In more sophisticated systems, a ramp is attached to the host vessel, typically at the bow or stern, and is lowered or otherwise extended so that the distal end of the ramp extends into the water. This latter system, which is best suited for tracked or wheeled sub-ordinate vessels or vehicles, allows the sub-ordinate vessel or vehicle to move down the ramp into the water to effect a launch, and, conversely, to move up the ramp onto the deck or into the interior of the host vessel to effect a recovery. In most cases, launch and recovery occurs while the host vessel is stopped or moving a relatively low forward speed.
While the prior ramp-type systems have functioned relatively satisfactorily for their intended purposes, the prior systems are not well-suited for sub-ordinate vessel recovery at higher speeds since the effects of surface and/or sub-surface currents, waves, and wind action on the two vehicles oftentimes can cause problems in positionally maintaining the alignment of the ramp relative to the sub-ordinate vessel to be launched or recovered. As can be appreciated, difficult-to-predict movements of the ramp relative to the sub-ordinate vessel during launch and/or recovery operations increases the probability of mishaps.